This invention relates to mobile platforms more especially but not exclusively the invention relates to mobile platforms for use in motion simulators such as automobile simulators.
Automobile simulators are useful for both pleasure purposes and for training and development work for motorsports teams as well as for general automotive development, driver training and electronic control unit software development and engineer training.
A conventional simulator typically comprises a parallel robot such a Stewart or Gough platform which comprises six linear actuators provided at each end with universal joints connected to a ground support and a platform. Appropriate actuation of the cylinders allows motion in all degrees of freedom and combinations thereof. Often these degrees of freedom are named using nautical terminology, for example:
1. Moving up and down (heaving);
2. Moving left and right (swaying));
3. Moving forward and backward (surging);
4. Tilting forward and backward (pitching);
5. Turning left and right (yawing); and
6. Tilting side to side (rolling).
A problem with a Stewart platform is that it is very bulky and may require a special building to accommodate it.
Some, especially automobile simulators, have fewer than six degrees of freedom with typically sway being omitted.
It is often neither necessary nor desirable for the simulator to reproduce exactly the motions which are simulated. The simulator may provide initial cues to the user replicating the initial motion and then reducing the inputs so that the movement limits of the platform are not exceeded. Nevertheless a simulator can be very large and yet still have movement limits exceeded. The invention seeks to provide a motion platform with both good movement limits but also relatively small bulk.